1. Field of the Invention
The present invention relates to a sheet feeder for feeding a sheet such as paper sheet (on which an image to be recorded or which has an image recorded thereon), and also a process of feeding the sheet in the sheet feeder.
2. Discussion of Related Art
On an image recording device such as printer and facsimile, there is installed a sheet feeder that is arranged to feed sheets accommodated in a sheet supply tray, along a feed path, as disclosed in JP-H08-119533A, for example.
In the conventional sheet feeder, in general, there are provided a sheet supply roller and a pair of sheet feed rollers. The sheet supply roller is disposed in an upstream portion of the feed path as viewed in a direction in which the sheet is to be fed along the feed path, and is configured to be held in pressing contact with an uppermost one of the sheets accommodated in the sheet supply tray. The sheet feed rollers are disposed in a downstream portion of the feed path, and consist of two rollers that are positioned on respective opposite sides of the feed path. Commonly, a DC motor is employed as a drive source for rotating the sheet supply roller and the sheet feed rollers.
As the DC motor as the drive source is driven, the sheet supply roller is rotated whereby the uppermost one of the sheets accommodated in the sheet supply tray is supplied toward the feed path. After a leading end of the sheet has reached a position of the sheet feed rollers, the sheet is nipped between the sheet feed rollers and is fed by the sheet feed rollers along the feed path. In this instance, the sheet feed rollers are intermittently driven or rotated, so as to feed the sheet in a sheet feed direction, with an amount of each intermittent feed movement of the sheet corresponding to an amount of line feed. In the image recording device incorporating therein such a sheet feeder, a recording head is moved in a main scanning direction (substantially perpendicular to the sheet feed direction) after each intermittent feed movement of the sheet, so that an image is recorded on the sheet that is thus fed by the amount of line feed in each intermittent feed movement thereof.